Inputs¶

—- If a file named quadrupole.fmt is present in the running directory, the code will use quadrupoles to perform the interpolation of the electron-phonon matrix elements and dynamical matrices. The structure of the file is as follow:

atom   dir       Qxx         Qyy         Qzz         Qyz         Qxz         Qxy
   1      XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX
   2      XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX
   3      XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX
   1      XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX
   2      XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX
   3      XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX    XXXXXXXX
...

where XXXXXXXX have to be replaced by the value of the quadrupoles which can be obtained, for example, using the ABINIT software

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`a2f`¶

Type	LOGICAL
Default	.false.
Description	Calculate Eliashberg spectral function, \(\alpha^2F(\omega)\), transport Eliashberg spectral function \(\alpha^2 F_{\rm tr}(\omega)\), and phonon density of states \(F(\omega)\). Only allowed in the case of phonselfen = .true.

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`amass(:)`¶

Variable	amass(i), i=1,ntyp
Type	REAL
Default	0.0
Description	Atomic mass [amu] of each atomic type. If not specified, masses are read from data file.

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`asr_typ`¶

Type	CHARACTER
Default	‘simple’
Description	Kind of acoustic sum rule that can be imposed in real space. Possible ASR are ‘simple’, ‘crystal’, ‘one-dim’ and ‘zero-dim’.

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`assume_metal`¶

Type	LOGICAL
Default	.false.
Description	Assume we have a metal. This flag should only be activated in the context of transport (conductivity or resistivity) calculations. In that case use a Fermi-Dirac distribution.

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`band_plot`¶

Type	LOGICAL
Default	.false.
Description	Writes files for band structure and phonon dispersion plots. The k-path and q-path is provided using filkf and filqf.

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`bands_skipped`¶

Type	CHARACTER
Default	`''`
Description	List of bands to exclude from the wannierization, where the number of excluded bands should be smaller or equal to nbndskip. For example, `bands_skipped = 'exclude_bands = 1:5'` means the first 5 bands are excluded from the wannierization.

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`bfieldx, bfieldy, bfieldz`¶

Type	REAL
Default	0.0
Description	The magnetic field in the x, y and z Cartesian directions in [Tesla].

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`bnd_cum`¶

Type	INTEGER
Default	1
Description	Band index for which the cumulant calculation is done. For more than one band, you need to perform multiple calculation and add the results together.

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`broyden_beta`¶

Type	REAL
Default	0.7
Description	Mixing factor for Broyden mixing scheme.

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`broyden_ndim`¶

Type	INTEGER
Default	8
Description	Number of iterations used in the Broyden mixing scheme.

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`carrier`¶

Type	LOGICAL
Default	.false.
Description	If .true. it computes the intrinsic electron or hole mobility such that the carrier concentration is given by ncarrier.

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`conv_thr_iaxis`¶

Type	REAL
Default	1.d-05
Description	Convergence threshold for iterative solution of imaginary-axis Eliashberg equations.

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`conv_thr_racon`¶

Type	REAL
Default	5.d-05
Description	Convergence threshold for iterative solution of the analytic continuation of Eliashberg equations from imaginary- to real-axis.

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`conv_thr_raxis`¶

Type	REAL
Default	5.d-04
Description	Convergence threshold for iterative solution of real-axis Eliashberg equations.

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`cumulant`¶

Type	LOGICAL
Default	.false.
Description	If .true. calculates the electron spectral function using the cumulant expansion method. Can be used as independent postprocessing by setting ep_coupling =.false.

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`degaussq`¶

Type	REAL
Default	0.05
Description	Smearing for sum over q in the e-ph coupling in [meV]

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`degaussw`¶

Type	REAL
Default	0.025
Description	Smearing in the energy-conserving delta functions in [eV]

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`delta_approx`¶

Type	LOGICAL
Default	.false.
Description	If .true. the double delta approximation is used to compute the phonon self-energy.

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`delta_qsmear`¶

Type	REAL
Default	0.05
Description	Change in the energy for each additional smearing in the a2f in [meV].

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`delta_smear`¶

Type	REAL
Default	0.01
Description	Change in the energy for each additional smearing in the phonon self-energy in [eV]

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`dvscf_dir`¶

Type	CHARACTER
Default	‘./’
Description	Directory where ‘prefix.[dvscf\|dyn]_q??’ files are located.

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`efermi_read`¶

Type	LOGICAL
Default	.false.
Description	If .true. the Fermi energy is read from the input file.

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`eig_read`¶

Type	LOGICAL
Default	.false.
Description	If .true. then read a set of eigenvalues from ksdata.fmt. Can be used to read GW (or other) eigenenergies. The code expect a file called “prefix.eig” to be read. One need to provide the same number of bands as in the nscf calculations and all k-points.

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`elecselfen`¶

Type	LOGICAL
Default	.false.
Description	Calculate the electron self-energy from the el-ph interaction

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`eliashberg`¶

Type	LOGICAL
Default	.false.
Description	If .true. solve the Eliashberg equations and/or calculate the Eliashberg spectral function. 1) if laniso =.true., the anisotropic Eliashberg equations are solved. This requires that .ephmat, .freq, .egnv, .ikmap files are read from the disk. The files are written when ephwrite =.true. in the input file (see ephwrite variable). 2) if liso =.true., the isotropic Eliashberg equations are solved. This requires that either (a) .ephmat, .freq, .egnv, .ikmap files (see ephwrite variable) or (b) isotropic Eliashberg spectral function file (see fila2f variable) are read from the disk. 3) if .not. laniso and .not. liso , the Eliashberg spectral function is calculated. This requires that .ephmat, .freq, .egnv, .ikmap files are read from the disk. The files are written when ephwrite =.true. in the input file (see ephwrite variable). Note: To reuse .ephmat, .freq, .egnv, .ikmap files obtained in a previous run, one needs to set ep_coupling =.false., elph =.false., and ephwrite =.false. in the input file.

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`elph`¶

Type	LOGICAL
Default	.false.
Description	If .true. calculate e-ph coefficients.

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`ep_coupling`¶

Type	LOGICAL
Default	.true.
Description	If .true. run e-ph coupling calculation.

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`epbwrite, epbread`¶

Type	LOGICAL
Default	.false.
Description	If epbwrite = .true., the electron-phonon matrix elements in the coarse Bloch representation and relevant data (dyn matrices) are written to disk. If epbread = .true. the above quantities are read from the ‘prefix.epb’ files. Pool dependent files.

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`epexst`¶

Type	LOGICAL
Default	.false.
Description	If .true. then prefix.epmatwp files are already on disk (don’t recalculate). This is a debugging parameter.

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`ephwrite`¶

Type	LOGICAL
Default	.false.
Description	Writes 4 files (in prefix.ephmat directory) that are required when solving the Eliashberg equations. ‘ephmatXX’ (XX: pool dependent files) files with e-ph matrix elements within the Fermi window (fsthick) on fine k and q meshes on the disk, ‘freq’ file contains the phonon frequencies, ‘egnv’ file contains the eigenvalues within the Fermi window, and ‘ikmap’ file contains the index of the k-point on the irreducible grid within the Fermi window. These files are required to solve the Eliashberg equations when eliashberg = .true.. The files can be reused for subsequent evaluations of the Eliashberg equations at different temperatures. ephwrite doesn’t work with random k- or q-meshes and requires nkf1,nkf2,nkf3 to be multiple of nqf1,nqf2,nqf3.

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`epmatkqread`¶

Type	LOGICAL
Default	.false.
Description	If .true. restart an IBTE calculation from scattering written to files.

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`eps_acustic`¶

Type	REAL
Default	5.d0
Description	The lower boundary for the phonon frequency in el-ph and a2f calculations in [cm-1].

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`epsiHEG`¶

Type	REAL
Default	0.25d0
Description	Dielectric constant at zero doping for electron-plasmon.

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`epwread`¶

Type	LOGICAL
Default	.false.
Description	If epwread = .true., the electron-phonon matrix elements in the coarse Wannier representation are read from the ‘epwdata.fmt’ and ‘XX.epmatwpX’ files. Each pool reads the same file. It is used for a restart calculation and requires kmaps = .true. A prior calculation with epwwrite = .true is also required.

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`epwwrite`¶

Type	LOGICAL
Default	.true.
Description	If epwwrite = .true., the electron-phonon matrix elements in the coarse Wannier representation and relevant data (dyn matrices) are written to disk. Each pool reads the same file.

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`etf_mem`¶

Type	INTEGER
Default	1
Description	If etf_mem = 0, then all the fine Bloch-space el-ph matrix elements are stored in memory (faster). When etf_mem = 1, more IO (slower) but less memory is required. When etf_mem = 2, an additional loop is done on mode for the fine grid interpolation part. This reduces the memory further by a factor “nmodes”.

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`fermi_diff`¶

Type	REAL
Default	1.d0
Description	Difference between Fermi energy and band edge (in eV). Only relevant when lscreen = .true.

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`fermi_energy`¶

Type	REAL
Default	0.d0
Description	Value of the Fermi energy read from the input file in [eV].

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`fermi_plot`¶

Type	LOGICAL
Default	.false.
Description	If .true., write Fermi surface files (in .cube format which can be plotted with VESTA) on nkf1, nkf2, nqf3.

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`fila2f`¶

Type	CHARACTER
Default	`''`
Description	Input file with isotropic Eliashberg spectral function. The file contains the Eliashberg spectral function as a function of frequency in [meV]. This file can only be used to calculate the isotropic Eliashberg equations. In this case `.ephmat`, `.freq`, `.egnv`, and `.ikmap` files are not required.

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`fildvscf`¶

Type	CHARACTER
Default	`''`
Description	Output file containing deltavscf (not used in calculation)

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`filkf`¶

Type	CHARACTER
Default	‘./’
Description	File which contains the fine k-mesh or the k-path of electronic states to be calculated for elinterp. Crystal coordinates.

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`filqf`¶

Type	CHARACTER
Default	‘./’
Description	File which contains the fine q-mesh or the q-path of phonon states to be calculated for phinterp. Crystal coordinates.

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`filukk`¶

Type	CHARACTER
Default	‘prefix.ukk’
Description	The name of the file containing the rotation matrix U(k) which describes the MLWFs.

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`filukq`¶

Type	CHARACTER
Default	‘prefix.ukq’
Description	The name of the file containing the rotation matrix U(k+q) which describes the MLWFs.

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`fixsym`¶

Type	LOGICAL
Default	.false.
Description	If .true. try to fix the symmetry-related issues.

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`fsthick`¶

Type	REAL
Default	1.d10
Description	Width of the Fermi surface window to take into account states in the self-energy delta functions in [eV]. Narrowing this value reduces the number of bands included in the selfenergy calculations.

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`gap_edge`¶

Type	REAL
Default	0.d0
Description	Initial guess for the superconducting gap edge if gap_edge .gt. 0.d0 in [eV]. Otherwise the initial guess for the gap is estimated based on the critical temperature found from the Allen-Dynes formula and BCS ratio (2*gap/T_c=3.52)

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`imag_read`¶

Type	LOGICAL
Default	.false.
Description	If .true. read from file the superdconducting gap and renormalization function on the imaginary-axis at a temperature XX. The required file is ‘prefix.imag_aniso_XX’. The temperature should be specified as temps(1) =XX in the input file. This flag works if limag =.true. and laniso =.true., and can be used to: (1) solve the Eliashberg equations on the real-axis with lpade =.true. or lacon =.true. starting from the imaginary-axis solutions at temperature XX; (2) solve the Eliashberg equations on the imaginary-axis at temperatures grater than XX using as a starting point the gap estimated at temperature XX. (3) write to file the superconducting gap on the Fermi surface in cube format at temperature XX. The output file is ‘prefix.imag_aniso_gap_XX_YY.cube’, where YY is the band number within the chosen energy window during the EPW calculation. The file is written if iverbosity =2.

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`int_mob`¶

Type	LOGICAL
Default	.false.
Description	If .true. and carrier = .false. it compute the intrinsic mobility such that the electron carrier concentration and hole concentration are the same (only one Fermi level) and give both electron and hole mobility in the same run. If the gap is too big, the number of carrier will be so small that the code will be unstable. If .true. and carrier = .true. it will compute the intrinsic electron and hole mobility with two Fermi level such that the electron and hole carrier concentration is ncarrier.

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`iterative_bte`¶

Type	LOGICAL
Default	.false.
Description	If .true. it compute the iterative Boltzmann Transport Equation (IBTE) intrinsic mobility such that the electron carrier concentration and hole concentration are the same (only one Fermi level) and give both electron and hole mobility in the same run. If the gap is too big, the number of carrier will be so small that the code will be unstable. If .true. and carrier = .true. it will compute the intrinsic electron and hole mobility with two Fermi level such that the electron and hole carrier concentration is ncarrier. Also see mob_maxiter. Note that the IBTE can only be solved on a homogeneous grid. You can use k-point symmetry to reduce the computational time with mp_mesh_k.

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`iverbosity`¶

Type	INTEGER
Default	0
Description	0 = short output 1 = verbose output. 2 = verbose output for the superconducting part only. 3 = verbose output for the electron-phonon part only [mode resolved linewidths etc..].

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`kerread`¶

Type	LOGICAL
Default	.false.
Description	If .true. read Kp and Km kernels from files .ker when solving the real-axis Eliashberg equations.

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`kerwrite`¶

Type	LOGICAL
Default	.false.
Description	If .true. write Kp and Km kernels to files .ker when solving the real-axis Eliashberg equations.

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`kmaps`¶

Type	LOGICAL
Default	.false.
Description	Generate the map k+q –> k for folding the rotation matrix U(k+q). If .true., the program reads ‘prefix.kmap’ and ‘prefix.kgmap’ from file. If .false., they are calculated. Note that for a restart with epwread =.true., kmaps also needs to be set to true (since the information to potentially calculate kgmaps is not generated in a restart run). However, the files “prefix.kmap” and “prefix.kgmap” themselves are actually not used if epwread=.true. and hence need not actually be there.

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`lacon`¶

Type	LOGICAL
Default	.false.
Description	If .true. an analytic continuation to continue the imaginary-axis Eliashberg equations to real-axis. This flag requires limag =.true. and lpade =.true.

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`laniso`¶

Type	LOGICAL
Default	.false.
Description	If .true. solve the anisotropic Eliashberg equations on the imaginary-axis. To solve the equations, `.ephmat`, `.freq`, `.egnv`, and `.ikmap` files should be provided. These files are described under ephwrite variable.

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`lifc`¶

Type	LOGICAL
Default	.false.
Description	If .true. uses the real-space inter-atomic force constant generated by q2r.x. The resulting file must be named “ifc.q2r”. The file has to be placed in the same directory as the dvscf files. In the case of SOC, the file must be named “ifc.q2r.xml” and be in xml format. See asr_typ for the type of acoustic sum rules that can be imposed.

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`limag`¶

Type	LOGICAL
Default	.false.
Description	If .true. solve the imaginary-axis Eliashberg equations.

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`lindabs`¶

Type	LOGICAL
Default	.false.
Description	If .true. computes indirect phonon absorption. See the input variables omegamax, omegamin, omegastep and n_r.

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`liso`¶

Type	LOGICAL
Default	.false.
Description	If .true. solve the isotropic Eliashberg equations on the real- or imaginary-axis. To solve the equations provide either: (1) Eliashberg spectral function file using fila2f variable. (2) `.ephmat`, `.freq`, `.egnv`, and `.ikmap` files. These files are described under ephwrite variable.

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`lpade`¶

Type	LOGICAL
Default	.false.
Description	If .true. Padé approximants to continue the imaginary-axis Eliashberg equations to real-axis. This works with limag =.true.

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`lphase`¶

Type	LOGICAL
Default	.false.
Description	If .true. then fix the gauge for the interpolated dynamical matrix and electronic Hamiltonian.

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`lpolar`¶

Type	LOGICAL
Default	.false.
Description	If .true. enable the correct Wannier interpolation in the case of polar material.

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`lreal`¶

Type	LOGICAL
Default	.false.
Description	If .true. solve the Eliashberg equations directly on the real-axis. Only the isotropic case (liso =.true.) is implemented.

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`lscreen`¶

Type	LOGICAL
Default	.false.
Description	If .true. the el-ph matrix elements are screened by the RPA or TF dielectric function. See (scr_typ).

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`lunif`¶

Type	LOGICAL
Default	.true.
Description	If .true. a uniform frequency grid is defined between (wsfc,wscut) for solving the real-axis Eliashberg equations. Works only with lreal =.true.

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`longrange`¶

Type	LOGICAL
Default	.false.
Description	If .true. only the long-range part of the electron-phonon matrix elements are calculated. Works only with lpolar =.true.

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`max_memlt`¶

Type	REAL
Default	2.85d0
Description	Maximum memory that can be allocated per pool in [Gb].

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`meff`¶

Type	REAL
Default	12.0
Description	Density of state effective mass for electron-plasmon.

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`mob_maxiter`¶

Type	INTEGER
Default	50
Description	Maximum number of iteration during the IBTE.

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`mp_mesh_k`¶

Type	LOGICAL
Default	.false.
Description	If .true., fine electronic mesh is in the irr. wedge, else a uniform grid throughout the BZ is used.

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`mp_mesh_q`¶

Type	LOGICAL
Default	.false.
Description	If .true., fine phonon mesh is in the irr. wedge, else a uniform grid throughout the BZ is used. Not currently in use.

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`nbndsub`¶

Type	INTEGER
Default	0
Description	Number of wannier functions to utilize.

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`ncarrier`¶

Type	REAL
Default	1.0d+13
Description	If carrier = .true. then compute the intrinsic mobility with ncarrier concentration (in cm^-3). If ncarrier is positive it will compute the electron mobility and if it is negative it will compute the hole mobility. If int_mob is also .true. then it will compute both the electron and hole mobility, which is the recommended way to compute mobility.

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`nc`¶

Type	REAL
Default	4.0d0
Description	Number of carriers per unit cell that participate to the conduction in the Ziman’s resistivity formula. Typically this corresponds to the number of bands crossing the Fermi level. This can be a fractional number.

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`nel`¶

Type	REAL
Default	0.01
Description	Carrier concentration for electron-plasmon.

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`nest_fn`¶

Type	LOGICAL
Default	.false.
Description	Calculate the electronic nesting function.

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`ngaussw`¶

Type	INTEGER
Default	1
Description	Smearing type for FS average after Wannier interpolation

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`nk1, nk2, nk3`¶

Type	INTEGER
Default	0
Description	Dimensions of the coarse electronic grid, corresponds to the nscf calculation and wfs in the outdir.

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`nkf1, nkf2, nqf3`¶

Type	INTEGER
Default	0
Description	Dimensions of the fine electron grid, if filkf is not given.

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`nq1, nq2, nq3`¶

Type	INTEGER
Default	0
Description	Dimensions of the coarse phonon grid, corresponds to the nqs list.

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`nqf1, nqf2, nqf3`¶

Type	INTEGER
Default	0
Description	Dimensions of the fine phonon grid, if filqf is not given.

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`npade`¶

Type	INTEGER
Default	90
Description	Percentage of Matsubara points used in Padé continuation.

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`nqsmear`¶

Type	INTEGER
Default	10
Description	Number of different smearings used to calculate the a2f.

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`nqstep`¶

Type	REAL
Default	500
Description	Number of steps used to calculate the a2f

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`n_r`¶

Type	REAL
Default	1.0
Description	Refractive index used when lindabs = .true.

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`nsiter`¶

Type	INTEGER
Default	40
Description	Number of iteration for the self-consistency cycle when solving the real- or imaginary-axis Eliashberg equations.

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`nsmear`¶

Type	INTEGER
Default	1
Description	Number of different smearings used to calculate the phonon self-energy.

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`nstemp`¶

Type	INTEGER
Default	1
Description	Number of temperature points used for superconductivitiy, transport, indabs, etc.. If nstemp is left blank, or is equivalent to the number of entries in temps(:), then the temperatures provided in temps(:) are used. If nstemp>2 and only two temperatures are given in temps(:), then an evenly spaced temperature grid with steps between points given by (temps(2) - temps(1)) / (nstemp-1) is generated. This grid contains nstemp points. nstemp cannot be larger than 50.

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`nswi`¶

Type	INTEGER
Default	0
Description	Number of frequency grid points when solving the imaginary-axis Eliashberg equations. If nswi > 0, wscut is ignored. Works only with limag =.true.

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`nswc`¶

Type	INTEGER
Default	0
Description	Number of frequency grid points between (wsfc, wscut) when solving the real-axis Eliashberg equations. Works only with lreal=.true.

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`nswfc`¶

Type	INTEGER
Default	0
Description	Number of frequency grid points between (0, wsfc) when solving the real-axis Eliashberg equations. Works only with lreal =.true.

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`muc`¶

Type	REAL
Default	0.d0
Description	Effective Coulomb potential used in the Eliashberg equations.

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`nw`¶

Type	INTEGER
Default	10
Description	Number of bins for frequency scan in delta( e_k - e_k+q - w).

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`nw_specfun`¶

Type	INTEGER
Default	100
Description	Number of bins for frequency in electron spectral function.

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`omegamax`¶

Type	REAL
Default	10
Description	Photon energy maximum (in eV) when lindabs = .true.

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`omegamin`¶

Type	REAL
Default	0
Description	Photon energy minimum (in eV) when lindabs = .true.

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`omegastep`¶

Type	REAL
Default	1
Description	Steps in photon energy (in eV) when lindabs = .true.

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`outdir`¶

Type	CHARACTER
Default	‘./’
Description	Scratch directory.

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`phonselfen`¶

Type	LOGICAL
Default	.false.
Description	Calculate the phonon self-energy from the el-ph interaction.

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`plselfen`¶

Type	LOGICAL
Default	.false.
Description	Calculate the electron-plasmon self-energy (model). It requires the definition of nel, meff and epsiHEG.

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`prefix`¶

Type	CHARACTER
Default	‘pwscf’
Description	Prepended to input/output filenames. Must be the same used in the calculation of the wfs and phonons.

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`prtgkk`¶

Type	LOGICAL
Default	.false.
Description	Allows to print the electron-phonon vertex \|g\| (in meV) for each q-point, k-point, i-band, j-band and modes. Note: Average over degenerate i-band, j-band and modes is performed but not on degenerate k or q-points. Warning: this produces huge text data in the main output file and considerably slows down the calculation. Suggestion: Use only 1 k-point (like Gamma).

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`pwc`¶

Type	REAL
Default	1.0
Description	Power used to define a non-uniform grid between (wsfc, wscut) when solving the real-axis Eliashberg equations. Works only if lreal =.true.

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`rand_nq, rand_nk`¶

Type	INTEGER
Default	1
Description	number of random q,k-vectors on the fine mesh

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`rand_q, rand_k`¶

Type	LOGICAL
Default	.false.
Description	q/k-vectors on the fine mesh are generated randomly

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`restart`¶

Type	LOGICAL
Default	.false.
Description	Create a restart point every restart_step q-points from the fine grid during the interpolation stage.

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`restart_filq`¶

Type	CHARACTER
Default	`''`
Description	Input file to restart from an exisiting q-file. Use to merge different q-grid scattering rates.

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`restart_step`¶

Type	INTEGER
Default	100
Description	Frequency of restart points during the fine q-grid interpolation phase. This produces restart files called XXX.sigma_restart1

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`scr_typ`¶

Type	INTEGER
Default	0
Description	If 0 calculates the Lindhard screening, if 1 the Thomas-Fermi screening. Only relevant if lscreen = .true.

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`scatread`¶

Type	LOGICAL
Default	.false.
Description	If .true. the current scattering rate file is read from file.

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`scattering`¶

Type	LOGICAL
Default	.false.
Description	If .true. computes scattering rates. See also scattering_serta for the type of scattering.

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`scattering_serta`¶

Type	LOGICAL
Default	.false.
Description	If .true. computes scattering rates in the self-energy relaxation time approximation. See S. Poncé, E. R. Margine and F. Giustino, Phys. Rev. B 97, 121201 (2018) for more information.

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`scattering_0rta`¶

Type	LOGICAL
Default	.false.
Description	If .true. then the scattering rates are calculated using 0th order relaxation time approximation.

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`scissor`¶

Type	REAL
Default	0.0
Description	Gives the value of the scissor shift of the gap (in eV).

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`selecqread`¶

Type	LOGICAL
Default	.false.
Description	If .true. then restart from the selecq.fmt file

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`smear_rpa`¶

Type	REAL
Default	0.05d0
Description	Smearing for the calculation of the Lindhard function (in eV). Only relevant if lscreen = .true.

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`specfun_el`¶

Type	LOGICAL
Default	.false.
Description	Calculate the electron spectral function from the e-ph interaction. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun.

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`specfun_ph`¶

Type	LOGICAL
Default	.false.
Description	Calculate the phonon spectral function from the e-ph interaction. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun.

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`specfun_pl`¶

Type	LOGICAL
Default	.false.
Description	Calculate electron-plasmon spectral function. The relevant variables in this case are wmin_specfun, wmax_specfun and nw_specfun. See also nel, meff, epsiHEG.

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`system_2d`¶

Type	LOGICAL
Default	.false.
Description	If .true. the system is two-dimensional (vaccum is in z-direction) and the k and q meshes are defined in the xy-plane.

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`shortrange`¶

Type	LOGICAL
Default	.false.
Description	If .true. then computes the short-range part of the electron-phonon matrix elements. Works only with lpolar =.true.

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`temps`¶

Type	REAL(nstemp)
Default	300.d0 Kelvin
Description	Temperature values used in superconductivitiy, transport, indabs, etc. in kelvin unit. If no temps are provided, temps=300 and nstemp =1. If two temps are provided, with temps(1)<temps(2) and nstemp >2, then temps is transformed into an evenly spaced grid with nstemp points, including temps(1) and temps(2) as the minimum and maximum values, respectively [Ex) `nstemp = 5` `temps = 300 500`]. In this case, points are spaced according to (temps(2) - temps(1)) / (nstemp-1). Otherwise, temps is treated as a list, with the given temperatures used directly [Ex) `temps = 17 20 30`]. No more than 50 temperatures can be supplied in this way.

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`tc_linear`¶

Type	LOGICAL
Default	.false.
Description	If .true. linearized Eliashberg eqn. for superconducting transition temperature Tc will be solved.

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`tc_linear_solver`¶

Type	CHARACTER
Default	‘power’
Description	Algorithm to solve Tc eigenvalue problem. Possible algorithms are ‘power’, and ‘lapack’.

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`vme`¶

Type	CHARACTER
Default	‘wannier’
Description	if ‘dipole’ then computes the velocity as dipole+commutator = <psi_mk\|p+i[V_NL,r]\|psi_nk>. If ‘wannier’ then computes the velocity as dH_nmk/dk - i(e_nk-e_mk)A_nmk where A is the Berry connection. Note: Before v5.4, vme = .FALSE. was the velocity in the local approximation as <psi_mk\|p\|psi_nk>. Before v5.4, vme = .TRUE. was the same as ‘wannier’.

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`wannierize`¶

Type	LOGICAL
Default	.false.
Description	Calculate the Wannier functions using W90 library calls and write rotation matrix to file ‘filukk’. If .false., filukk is read from disk.

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`wepexst`¶

Type	LOGICAL
Default	.false.
Description	If .true. then prefix.epmatwe files are already on disk (don’t recalculate). This is a debugging parameter.

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`wmax`¶

Type	REAL
Default	0.3d0
Description	Max frequency in delta( e_k - e_k+q - w).

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`wmax_specfun`¶

Type	REAL
Default	0.d0
Description	The upper boundary for the frequency in the electron spectral function in [eV].

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`wmin`¶

Type	REAL
Default	0.d0
Description	Min frequency in delta( e_k - e_k+q - w).

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`wmin_specfun`¶

Type	REAL
Default	0.d0
Description	The lower boundary for the frequency in the electron spectral function in [eV].

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`wscut`¶

Type	REAL
Default	1.d0
Description	Upper limit over frequency integration/summation in the Eliashberg equations in [eV]. For limag =.true., wscut is ignored if the number of frequency points is given using variable nswi.

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`wsfc`¶

Type	REAL
Default	0.5 * wscut
Description	Intermediate frequency between (0, wscut) in the integration of the real-axis Eliashberg equations in [eV]. Works only with lreal =.true.

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`auto_projections`¶

Type	LOGICAL
Default	.false.
Description	If .true. then automatically generate initial projections for Wannier90. It requires :ref:`scdm_proj`=.true.

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`dis_froz_min, dis_froz_max`¶

Type	REAL
Default	-1d3, -0.9d3
Description	Window which includes frozen states for Wannier90. See wannier90 documentation.

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`dis_win_max`¶

Type	REAL
Default	-1d3, 1d3
Description	Maximum value of the outer window. See wannier90 documentation.

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`iprint`¶

Type	INTEGER
Default	2
Description	Verbosity level of Wannier90 code. See wannier90 documentation.

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`num_iter`¶

Type	INTEGER
Default	200
Description	Number of iterations passed to Wannier90 for minimization. See wannier90 documentation.

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`proj(:)`¶

Type	CHARACTER
Default	`''`
Description	Initial projections used in the Wannier90 calculation. Simple solution is `proj(1) = 'random'`. See wannier90 documentation.

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`reduce_unk`¶

Type	LOGICAL
Default	.false.
Description	If .true. then plot Wannier functions on reduced grids.

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`scdm_entanglement`¶

Type	CHARACTER
Default	‘isolated’
Description	Disentanglement type in the SCDM algorithm.

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`scdm_mu`¶

Type	REAL
Default	0.d0
Description	Parameter for Wannier functions via SCDM algorithm.

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`scdm_proj`¶

Type	LOGICAL
Default	.false.
Description	If .true. then calculate MLWFs without an initial guess via the SCDM algorithm.

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`scdm_sigma`¶

Type	REAL
Default	1.d0
Description	Parameter for Wannier functions via SCDM algorithm.

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`wannier_plot`¶

Type	LOGICAL
Default	.false.
Description	If .true. then plot Wannier functions.

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`wannier_plot_list`¶

Type	CHARACTER
Default	`''`
Description	Field read for parsing Wannier function list.

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`wannier_plot_radius`¶

Type	REAL
Default	3.5d0
Description	Cut-off radius for plotting Wannier functions.

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`wannier_plot_scale`¶

Type	REAL
Default	1.0d0
Description	Scaling parameter for cube files.

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`wannier_plot_supercell`¶

Type	INTEGER(3)
Default	(/5,5,5/)
Description	Size of supercell for plotting Wannier functions

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`wdata(:)`¶

Type	CHARACTER
Default	`''`
Description	Any extra inforumation to be used in the Wannier90 calculation should be included here. These characters will be written to the ‘prefix.win’ file. For example to plot the first Wannier function in xcrysden format: —————————————————– `wdata(1) = 'wannier_plot = true'` `wdata(2) = 'wannier_plot_list : 1'` —————————————————– See wannier90 documentation.

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Inputs¶

List of inputs of EPW v5.4¶

Structure of the input data¶

&inputepw¶

a2f¶

amass(:)¶

asr_typ¶

assume_metal¶

band_plot¶

bands_skipped¶

bfieldx, bfieldy, bfieldz¶

bnd_cum¶

broyden_beta¶

broyden_ndim¶

carrier¶

conv_thr_iaxis¶

conv_thr_racon¶

conv_thr_raxis¶

cumulant¶

degaussq¶

degaussw¶

delta_approx¶

delta_qsmear¶

delta_smear¶

dvscf_dir¶

efermi_read¶

eig_read¶

elecselfen¶

eliashberg¶

elph¶

ep_coupling¶

epbwrite, epbread¶

epexst¶

ephwrite¶

epmatkqread¶

eps_acustic¶

epsiHEG¶

epwread¶

epwwrite¶

etf_mem¶

fermi_diff¶

fermi_energy¶

fermi_plot¶

fila2f¶

fildvscf¶

filkf¶

filqf¶

filukk¶

filukq¶

fixsym¶

fsthick¶

gap_edge¶

imag_read¶

int_mob¶

iterative_bte¶

iverbosity¶

kerread¶

kerwrite¶

kmaps¶

lacon¶

laniso¶

lifc¶

limag¶

lindabs¶

liso¶

lpade¶

lphase¶

lpolar¶

lreal¶

lscreen¶

lunif¶

longrange¶

max_memlt¶

meff¶

mob_maxiter¶

mp_mesh_k¶

mp_mesh_q¶

nbndsub¶

ncarrier¶

nc¶

`a2f`¶

`amass(:)`¶

`asr_typ`¶

`assume_metal`¶

`band_plot`¶

`bands_skipped`¶

`bfieldx, bfieldy, bfieldz`¶

`bnd_cum`¶

`broyden_beta`¶

`broyden_ndim`¶

`carrier`¶

`conv_thr_iaxis`¶

`conv_thr_racon`¶

`conv_thr_raxis`¶

`cumulant`¶

`degaussq`¶

`degaussw`¶

`delta_approx`¶

`delta_qsmear`¶

`delta_smear`¶

`dvscf_dir`¶

`efermi_read`¶

`eig_read`¶

`elecselfen`¶

`eliashberg`¶

`elph`¶

`ep_coupling`¶

`epbwrite, epbread`¶

`epexst`¶

`ephwrite`¶

`epmatkqread`¶

`eps_acustic`¶

`epsiHEG`¶

`epwread`¶

`epwwrite`¶

`etf_mem`¶

`fermi_diff`¶

`fermi_energy`¶

`fermi_plot`¶

`fila2f`¶

`fildvscf`¶

`filkf`¶

`filqf`¶

`filukk`¶

`filukq`¶

`fixsym`¶

`fsthick`¶

`gap_edge`¶

`imag_read`¶

`int_mob`¶

`iterative_bte`¶

`iverbosity`¶

`kerread`¶

`kerwrite`¶

`kmaps`¶

`lacon`¶

`laniso`¶

`lifc`¶

`limag`¶

`lindabs`¶

`liso`¶

`lpade`¶

`lphase`¶

`lpolar`¶

`lreal`¶

`lscreen`¶

`lunif`¶

`longrange`¶

`max_memlt`¶

`meff`¶

`mob_maxiter`¶

`mp_mesh_k`¶

`mp_mesh_q`¶

`nbndsub`¶

`ncarrier`¶

`nc`¶

`nel`¶

`nest_fn`¶

`ngaussw`¶

`nk1, nk2, nk3`¶